Google is developing an anonymous identifier for advertisers that could give you more privacy and control over how you’re tracked online.

The Mountain View, Calif. company, which saw $43.7 billion in ad revenue last year, is considering replacing third-party cookies used to tailor ads to consumers’ interest with an anonymous identifier to track people’s browsing activity, USA Today reports. The plans, not yet made public by Google, could receive backlash from advertisers for giving more power to the search giant in the $120 billion digital ad industry.

“They could deprecate the use of that ID on a whim basically, and severely undermine billions of dollars in digital ad spending,” Mike Zaneis, the Interactive Advertising Bureau’s general counsel, told the newspaper. The IAB has also been petitioning Mozilla for its plans to block third-party cookies in Firefox by default.